1. Field of the Invention
The present invention relates to a cassette-based recording/reproducing apparatus having a holding mechanism in which a resilient engagement member engages a fitting portion formed on the cassette to hold the cassette in place within a cassette holder.
2. Prior Art
FIGS. 6-9 show a conventional cassette-based recording/reproducing apparatus disclosed in Japanese Patent Preliminary Publication No. 62-209762. FIG. 6 is a perspective view of a digital audio tape recorder (DAT), one type of the cassette-based recording/reproducing apparatus into which the cassette 1 is about to be inserted. FIG. 7 is a cross-sectional view of core elements of this DAT when the cassette has been inserted into a cassette-inserting position. FIG. 8 is a perspective view of the cassette-based recording/reproducing apparatus where the cassette holder 2 is on the part way when it is being moved toward a cassette-loading position and FIG. 9 is a cross-sectional view of the core elements in FIG. 8. In the figures, a cassette 1 is formed with a recess 5 on the surface thereof which acts as a fitting portion. The cassette holder 2 moves between the cassette-inserting position (shown in FIG. 7) and the cassette-loading position (not shown). A retaining spring 3 is secured to the cassette holder 2 to retain the cassette 1 in the cassette holder 2. A base 4 is formed with a guiding slot 4a therein for guiding the cassette holder 2.
A resilient engagement member 6 is formed of a leaf spring 6a and a hook 6b attached to the tip end of the leaf spring 6a, and is mounted to the cassette holder 2 such that the leaf spring 6a deflects resiliently. The hook 6b has two wings 6d extending transversely of the leaf spring 6a and beveled surfaces 6c. An arm 7 is made of a non-resilient material and functions as a disengaging member.
The operation of the above-mentioned prior art DAT will be described below. When the cassette 1 is inserted in a direction of arrow A, the cassette 1 is urged against the cassette holder 2 by the retaining spring 3 to be held in sandwiched relation between the cassette holder 2 and the retaining spring 3. The beveled surface 6c of the resilient engagement member 6 engages the beveled surface 7a of an arm 7 to climb up the surface 7a. At this cassette-inserting position, wings 6d of the resilient engagement member 6 ride on the arms 7 and is deflected as depicted by solid lines in FIG. 11; therefore the hook 6b is out of engagement with the recess 5. Then, when the cassette holder 2 is moved by a drive source (not shown) from the cassette-inserting position in a direction of arrow B shown in FIG. 7, the wing 6d slides on the arm 7 in a direction of C as shown in FIG. 9. The hook 6b will eventually slide off the arm 7 to engage the recess 5 of the cassette 1 with the aid of the urging force of the leaf spring 6a, thereby fixing the cassette 1 in the cassette holder 2.
When the cassette 1 is to be taken out of the apparatus, the cassette holder 2 is moved by the drive source (not shown) from the cassette-loading position back to the cassette-inserting position causing the beveled surface 6c to engage the tip end of the arm 7 to climb up the beveled surface 7a. Thus, the hook 6b again takes up the position (cassette-inserting position) shown in FIG. 7 to become out of engagement with the recess 5, leaving the cassette holder 2 held only by the urging force of the retaining spring 3 at the cassette-inserting position. Thereafter the cassette 2 is taken out manually from the cassette holder 2.
To ensure that the wing 6c climbs the tip end surface 7a for causing the hook 6b to move out of engagement with the recess 5, a clearance D is required between the base 4 and the cassette holder 2 as shown in FIG. 7. If the clearance D is to be reduced for the reduced overall height of the apparatus, then the problem is that the arm 7 extends into the cassette holder 2 to block the movement of the cassette holder 2 when the cassette holder 2 is moved from the cassette loading position to the cassette-inserting position in a direction of arrow E as shown in FIG. 10.